Re: [PATCH 1/3] Adding Skyworks SKY81452 MFD driver

Gyungoh Yoo
2014-08-25T07:06:19Z

Thank you for reviewing the patches.

On Thu, Aug 21, 2014 at 10:45:02AM +0100, Lee Jones wrote:
> When you send patch-sets, you should send them connected to one
> another AKA threaded. That way, when we're reviewing we can look at
> the other patches in the set for reference. See the man page for `git
> send-email` for details.
>
> <commit log>
>
> > Signed-off-by: Gyungoh Yoo <jack.yoo@skyworksinc.com>
> > ---
> > Documentation/devicetree/bindings/mfd/sky81452.txt | 24 +++++
>
> Binding documents should be sent separately:
>
> See: Documentation/devicetree/bindings/submitting-patches.txt
>
> > .../devicetree/bindings/vendor-prefixes.txt | 1 +
>
> This can go in with the documentation.

I see. I will re-send them separately.

>
> > drivers/mfd/Kconfig | 12 +++
> > drivers/mfd/Makefile | 1 +
> > drivers/mfd/sky81452.c | 113 +++++++++++++++++++++
> > include/linux/mfd/sky81452.h | 32 ++++++
> > 6 files changed, 183 insertions(+)
> > create mode 100644 Documentation/devicetree/bindings/mfd/sky81452.txt
> > create mode 100644 drivers/mfd/sky81452.c
> > create mode 100644 include/linux/mfd/sky81452.h
> >
> > diff --git a/Documentation/devicetree/bindings/mfd/sky81452.txt b/Documentation/devicetree/bindings/mfd/sky81452.txt
> > new file mode 100644
> > index 0000000..5fb0b4f
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/mfd/sky81452.txt
> > @@ -0,0 +1,24 @@
> > +SKY81452 bindings
> > +
> > +Required properties:
> > +- compatible : Must be "skyworks,sky81452"
> > +
> > +Required child nodes:
> > +- backlight : container node for backlight following the binding
> > + in video/backlight/sky81452-backlight.txt
> > +- regulator : container node for regulators following the binding
> > + in regulator/sky81452-regulator.txt
> > +
> > +Example:
> > +
> > + sky81452@2C {
>
> Lower case.
>
> > + compatible = "skyworks,sky81452";
>
> "reg"?
>
> You also need to document the 'compatible' and 'reg' properties.
>
> > + backlight {
> > + ...
> > + };
> > +
> > + regulator {
> > + ...
> > + };
> > + };
>
> I think it would be helpful to place a fully populated example in
> here.

I will update it.

>
> > diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
> > index d415b38..ce76e10 100644
> > --- a/Documentation/devicetree/bindings/vendor-prefixes.txt
> > +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
> > @@ -122,6 +122,7 @@ silabs Silicon Laboratories
> > simtek
> > sii Seiko Instruments, Inc.
> > sirf SiRF Technology, Inc.
> > +skyworks Skyworks Solutions, Inc.
> > smsc Standard Microsystems Corporation
> > snps Synopsys, Inc.
> > spansion Spansion Inc.
> > diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> > index de5abf2..acfb2e5 100644
> > --- a/drivers/mfd/Kconfig
> > +++ b/drivers/mfd/Kconfig
> > @@ -626,6 +626,18 @@ config MFD_SM501_GPIO
> > lines on the SM501. The platform data is used to supply the
> > base number for the first GPIO line to register.
> >
> > +config SKY81452
>
> MFD_SKY81452
>
> > + tristate "Skyworks Solutions SKY81452"
> > + select MFD_CORE
> > + select REGMAP_I2C
> > + depends on I2C=y
>
> Why do you need I2C to be built-in, rather than as a module?

It will depend only on I2C.

>
> > + help
> > + This is the core driver for the Skyworks SKY81452 backlight and
> > + voltage regulator device.
> > +
> > + This driver can also be built as a module. If so, the module
> > + will be called sky81452.
> > +
> > config MFD_SMSC
> > bool "SMSC ECE1099 series chips"
> > depends on I2C=y
> > diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> > index f001487..191c656 100644
> > --- a/drivers/mfd/Makefile
> > +++ b/drivers/mfd/Makefile
> > @@ -169,6 +169,7 @@ obj-$(CONFIG_MFD_AS3711) += as3711.o
> > obj-$(CONFIG_MFD_AS3722) += as3722.o
> > obj-$(CONFIG_MFD_STW481X) += stw481x.o
> > obj-$(CONFIG_MFD_IPAQ_MICRO) += ipaq-micro.o
> > +obj-$(CONFIG_SKY81452) += sky81452.o
> >
> > intel-soc-pmic-objs := intel_soc_pmic_core.o intel_soc_pmic_crc.o
> > obj-$(CONFIG_INTEL_SOC_PMIC) += intel-soc-pmic.o
> > diff --git a/drivers/mfd/sky81452.c b/drivers/mfd/sky81452.c
> > new file mode 100644
> > index 0000000..566912f
> > --- /dev/null
> > +++ b/drivers/mfd/sky81452.c
> > @@ -0,0 +1,113 @@
> > +/*
> > + * sky81452.c SKY81452 MFD driver
> > + *
> > + * Copyright 2014 Skyworks Solutions Inc.
> > + * Author : Gyungoh Yoo <jack.yoo@skyworksinc.com>
> > + *
> > + * This program is free software; you can redistribute it and/or modify it
> > + * under the terms of the GNU General Public License as published by the
> > + * Free Software Foundation; either version 2, or (at your option) any
> > + * later version.
> > + *
> > + * This program is distributed in the hope that it will be useful, but
> > + * WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> > + * General Public License for more details.
> > + *
> > + * You should have received a copy of the GNU General Public License along
> > + * with this program; if not, see <http://www.gnu.org/licenses/>.
> > + */
> > +
> > +#include <linux/kernel.h>
> > +#include <linux/module.h>
> > +#include <linux/init.h>
> > +#include <linux/err.h>
> > +#include <linux/slab.h>
> > +#include <linux/i2c.h>
> > +#include <linux/regmap.h>
> > +#include <linux/mfd/core.h>
> > +#include <linux/mfd/sky81452.h>
> > +
> > +static const struct regmap_config sky81452_config = {
> > + .reg_bits = 8,
> > + .val_bits = 8,
> > +};
> > +
> > +static int sky81452_register_devices(struct device *dev,
> > + const struct sky81452_platform_data *pdata)
> > +{
> > + struct mfd_cell cells[] = {
> > + {
> > + .name = "sky81452-bl",
> > + .platform_data = pdata->bl_pdata,
> > + .pdata_size = sizeof(*pdata->bl_pdata),
>
> Have you tested this with DT?
>
> You're not passing the compatible string and not using
> of_platform_populate() so I'm struggling to see how it would work
> properly.

sky81452-bl and regulator-sky81452 is parsing the information
in regulator node of its parent node. So I thought these 2 drivers
don't need compatible attribute. That is what it didn't have
compatible string.
Is is mandatory that all drivers should have compatible attribute?

>
> > + },
> > + {
> > + .name = "sky81452-regulator",
> > + .platform_data = pdata->regulator_init_data,
> > + .pdata_size = sizeof(*pdata->regulator_init_data),
> > + },
> > + };
>
> Please declare this outside of the function?

I see.

>
> > + return mfd_add_devices(dev, -1, cells, ARRAY_SIZE(cells),
> > + NULL, 0, NULL);
>
> This doesn't really need to be in a function of its own. Please put
> it in .probe(). Also check for the return value and present the user
> with an error message if it fails.

I think this need to be, in case of !CONFIG_OF.
Can you please explain more in details?

>
> > +}
> > +
> > +static int sky81452_probe(struct i2c_client *client,
> > + const struct i2c_device_id *id)
>
> Line up against '('.
>
> > +{
> > + struct device *dev = &client->dev;
> > + const struct sky81452_platform_data *pdata = dev_get_platdata(dev);
> > + struct regmap *map;
>
> Can you call this 'regmap' for clarity.

I see. Thank you.

>
> > + if (!pdata) {
> > + pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
> > + if (!pdata)
> > + return -ENOMEM;
> > + }
> > +
> > + map = devm_regmap_init_i2c(client, &sky81452_config);
> > + if (IS_ERR(map))
> > + return PTR_ERR(map);
>
> I'm not sure you want this to fail silently.
>
> > + i2c_set_clientdata(client, map);
> > +
> > + return sky81452_register_devices(dev, pdata);
> > +}
> > +
> > +static int sky81452_remove(struct i2c_client *client)
> > +{
> > + mfd_remove_devices(&client->dev);
> > + return 0;
> > +}
> > +
> > +static const struct i2c_device_id sky81452_ids[] = {
> > + { "sky81452", 0 },
>
> Remove the second attribute, it's unused.
>
> > + { }
> > +};
> > +MODULE_DEVICE_TABLE(i2c, sky81452_ids);
> > +
> > +#ifdef CONFIG_OF
> > +static const struct of_device_id sky81452_of_match[] = {
> > + { .compatible = "skyworks,sky81452", },
> > + { }
> > +};
> > +MODULE_DEVICE_TABLE(of, sky81452_of_match);
> > +#endif
>
> You can drop the #differy the compiler should sort that out on the
> back of of_match_ptr().
>
> > +static struct i2c_driver sky81452_driver = {
> > + .driver = {
> > + .name = "sky81452",
> > + .of_match_table = of_match_ptr(sky81452_of_match),
> > + },
> > + .probe = sky81452_probe,
> > + .remove = sky81452_remove,
> > + .id_table = sky81452_ids,
> > +};
> > +
> > +module_i2c_driver(sky81452_driver);
> > +
> > +MODULE_DESCRIPTION("Skyworks SKY81452 MFD driver");
> > +MODULE_AUTHOR("Gyungoh Yoo <jack.yoo@skyworksinc.com>");
> > +MODULE_LICENSE("GPL");
>
> I think you want v2.
>
> > +MODULE_VERSION("1.0");
> > diff --git a/include/linux/mfd/sky81452.h b/include/linux/mfd/sky81452.h
> > new file mode 100644
> > index 0000000..8d8ed35
> > --- /dev/null
> > +++ b/include/linux/mfd/sky81452.h
> > @@ -0,0 +1,32 @@
> > +/*
> > + * sky81452.h SKY81452 backlight driver
>
> If it's a just a backlight driver, why is it in MFD?
>
> You'd best expand the description here.

Sorry about that. I missed it.

>
> > + * Copyright 2014 Skyworks Solutions Inc.
> > + * Author : Gyungoh Yoo <jack.yoo@skyworksinc.com>
> > + *
> > + * This program is free software; you can redistribute it and/or modify it
> > + * under the terms of the GNU General Public License as published by the
> > + * Free Software Foundation; either version 2, or (at your option) any
> > + * later version.
> > + *
> > + * This program is distributed in the hope that it will be useful, but
> > + * WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> > + * General Public License for more details.
> > + *
> > + * You should have received a copy of the GNU General Public License along
> > + * with this program; if not, see <http://www.gnu.org/licenses/>.
> > + */
> > +
> > +#ifndef _SKY81452_H
> > +#define _SKY81452_H
> > +
> > +#include "linux/sky81452-backlight.h"
> > +#include "linux/regulator/machine.h"
>
> s/"/< and >
>
> > +struct sky81452_platform_data {
> > + struct sky81452_bl_platform_data *bl_pdata;
> > + struct regulator_init_data *regulator_init_data;
> > +};
> > +
> > +#endif
>
> --
> Lee Jones
> Linaro STMicroelectronics Landing Team Lead
> Linaro.org │ Open source software for ARM SoCs
> Follow Linaro: Facebook | Twitter | Blog